1 //===-- XCoreSelectionDAGInfo.cpp - XCore SelectionDAG Info ---------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the XCoreSelectionDAGInfo class.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #define DEBUG_TYPE "xcore-selectiondag-info"
15 #include "XCoreTargetMachine.h"
16 using namespace llvm;
17 
18 XCoreSelectionDAGInfo::XCoreSelectionDAGInfo(const XCoreTargetMachine &TM)
19   : TargetSelectionDAGInfo(TM) {
20 }
21 
22 XCoreSelectionDAGInfo::~XCoreSelectionDAGInfo() {
23 }
24 
25 SDValue XCoreSelectionDAGInfo::
26 EmitTargetCodeForMemcpy(SelectionDAG &DAG, SDLoc dl, SDValue Chain,
27                         SDValue Dst, SDValue Src, SDValue Size, unsigned Align,
28                         bool isVolatile, bool AlwaysInline,
29                         MachinePointerInfo DstPtrInfo,
30                         MachinePointerInfo SrcPtrInfo) const
31 {
32   unsigned SizeBitWidth = Size.getValueType().getSizeInBits();
33   // Call __memcpy_4 if the src, dst and size are all 4 byte aligned.
34   if (!AlwaysInline && (Align & 3) == 0 &&
35       DAG.MaskedValueIsZero(Size, APInt(SizeBitWidth, 3))) {
36     const TargetLowering &TLI = *DAG.getTarget().getTargetLowering();
37     TargetLowering::ArgListTy Args;
38     TargetLowering::ArgListEntry Entry;
39     Entry.Ty = TLI.getDataLayout()->getIntPtrType(*DAG.getContext());
40     Entry.Node = Dst; Args.push_back(Entry);
41     Entry.Node = Src; Args.push_back(Entry);
42     Entry.Node = Size; Args.push_back(Entry);
43 
44     TargetLowering::CallLoweringInfo
45     CLI(Chain, Type::getVoidTy(*DAG.getContext()), false, false, false, false,
46         0, TLI.getLibcallCallingConv(RTLIB::MEMCPY), /*isTailCall=*/false,
47         /*doesNotRet=*/false, /*isReturnValueUsed=*/false,
48         DAG.getExternalSymbol("__memcpy_4", TLI.getPointerTy()), Args, DAG, dl);
49     std::pair<SDValue,SDValue> CallResult =
50       TLI.LowerCallTo(CLI);
51     return CallResult.second;
52   }
53 
54   // Otherwise have the target-independent code call memcpy.
55   return SDValue();
56 }
57